1. Technical Field
The present invention relates generally to absorbent materials and processes for the manufacture thereof; and, more particularly, to shot-like absorbent materials which, despite their exterior appearance resembling pellets or buckshot, are, nonetheless, characterized by an open, porous fiber structure containing less than 30%, and preferably not more than 10% inorganic solids or "fillers" by weight and a low bulk density of less than 30 lbs./ft..sup.3 and, preferably, in the range of not more than 15 to 18 lbs./ft..sup.3. Shot-like absorbent materials made in accordance with the present invention are readily degradable by incineration or the like following usage as an absorbent; and, may be either hydrophilic or hydrophobic--e.g., oleophitic--in nature, thereby permitting usage of the hydrophilic forms of the invention as industrial floor sweeps, beddings for use with small animals, kitty litter and the like, while permitting usage of the hydrophobic forms of the invention for species specific absorption purposes such, merely by way of example, as the absorption of oil spills from both land and water environments, as well as absorption of other toxic liquid and/or odoriferous materials and/or other liquid contaminants.
More specifically, the present invention utilizes, as a basic ingredient, cellulose fibers of the type commonly generated in wood pulping, paper making or paper recycling operations; and, more particularly, cellulose fibers having a relatively low content of inorganic solids--e.g., clays and/or other silica compounds, commonly referred to as "fillers". Preferably, the cellulose fibers used with the present invention include not more than 10% inorganic solids by weight and, in any event, less than 30% inorganic solids by weight. Ideally, however, the cellulose fibers employed with the present invention have no inorganic solids content; but, as a practical matter, waste or process streams from most pulp and/or paper mills will include some inorganic solids or "fillers". Typically, such cellulose fiber materials having relatively low inorganic solids content are generated as a waste bi-product at the discharge end of a sulfite bleach mill used in the pulping industry such, for example, as in the pulp mill of Georgia Pacific Corporation located in Bellingham, Wash. However, as the ensuing description proceeds, those skilled in the art will appreciate that the invention is not limited to use with the discharge wastes of sulfite bleach pulp mills but, rather, can be used with cellulose fiber materials generated in other conventional pulping and/or paper making and/or recycling processes that produce streams containing cellulose fibers wherein the streams have low inorganic solids content.